longing for a child – one step closer to fulfil that desire by IMSI

About 15 % of all couples experience difficulties with achieving pregnancy as planned. In most of the cases the only solution is artificial fertilization of egg-cells with the partner’s semen after ovarian stimulation and retrieval of all present oocytes. To achieve high pregnancy rates by IVF treatment, it is essential to perform blastocyst selection on day 5 of development in culture. Up to now it was assumed that embryonic development depends mainly on the quality of the oocytes, which is declining with increasing female age. The semen, was thought of as only contributing its genome. It is not exactly like that. Our team (first author Dr. Pierre Vanderzwalmen) was the first to show very recently in a scientific publication released in RBMonline, a renowned international journal, that the semen is indeed contributing a lot more to embryonic development than only passing on its genes. We want to focus on the fact, that these findings were only possible, because we were in the position to observe the development of all embryos up to blastocyst stage, which is commonly referred to as blastocyst selection.

Usually “Intracytoplasmic Sperm Injection” in the following abbreviated by ICSI is a technique to inject the partner’s semen directly into the oocyte to achieve fertilization. This technique is especially applied when dealing with suboptimal sperm quality (male subfertility) and the sperm fails to fertilize the oocyte on its own. (referred to as in vitro fetrilization or IVF). In many couples having the desire for children the semen of the male partner is of suboptimal quality.
Our findings as follows:
Applying the ICSI technique to fertilize oocytes, it is only possible to perform semen assessment up to a 400-fold magnification in order to choose the best sperm cells. (Strictly speaking this is a matter of ‘selecting ‘ the best semen).

With the help of the so-called ‘Intracytoplasmic Morphologically Selected Sprem Injection ‘, in the following abbreviated by IMSI, a state of the art technique, it is now possible to perform a much better estimation of the semen, for the sperm cells can be observed at a 6.600 – 12.500 fold magnification. (Just imagine looking at the moon’s surface through a pair of binoculars. It goes without saying that this is completely different from observing the moon’s surface through the Hubble Space Telescope instead of using opera glasses). Well, by means of this new IMSI technique we were able to demonstrate that even in the case of a ‘normal’ semen analysis, there were significant differences in quality that could have never been detected by applying ICSI only (please see Figure 3 of original dissertation). On average 50 % of the semen is of bad quality. The worse the semen analysis is, the fewer sperm cells of good quality are to be found. We were able to establish a new classification for semen quality by means of the IMSI technique (semen quality 1 – 4). When using semen of quality 1 – 2 for fertilization, significantly more embryos develop up to blastocyst stage than by using semen of quality 3 – 4. Interestingly enough, this significance isn’t really obvious on day 3 of embryo development. Our findings allow us to conclude that in addition to blastocyst selection, semen selection should be performed, at any rate. In most of the cases, semen of quality 1 – 2 is to be found. Please note: Detection of semen quality 1 - 2 is only possible by means of the IMSI technique.

Attached please find original summary of published dissertation

Vanderzwalmen P, Hiemer A, Rubner P, Bach M, Neyer A, Stecher A, Uher P, Zintz M, Lejeune B, Vanderzwalmen S, Cassuto G, Zech NH. Blastocyst development after sperm selection at high magnification is associated with size and number of nuclear vacuoles. Reprod Biomed Online. 2008; 17(5): 617-27.

Institute for Reproductive Medicine and Endocrinology, Bregenz, Austria.
pierrevdz@hotmail.com

Spermatozoa selection at high magnification before intracytoplasmic sperm
injection seems to be positively associated with pregnancy rates after day 3 embryo transfers. The aim was to demonstrate an association between the presence of vacuoles in sperm nuclei and the competence of embryos to develop to day 5. Grading of spermatozoa at x 6000-x 12,500 magnification: grade I, no vacuoles; grade II, or=1 large vacuole; grade IV, large vacuoles with other abnormalities. The outcome of embryo development in a group of 25 patients after sibling oocyte injection with the four different grades of spermatozoa showed no significant difference in embryo quality up to day 3. However, the occurrence of blastocyst formation was 56.3 and 61.4% with grade I
and II spermatozoa respectively, compared with 5.1% with grade III and 0% with grade IV respectively (P < 0.001). Spermatozoa selection at high magnification using Nomarski interference contrast is useful to identify more precisely the size and the number of nuclear vacuoles that greatly exert a negative effect on embryo development to the blastocyst stage. These observations confirm previous studies pointing to possible 'early and late paternal effects', both of which may have an impact on early embryonic development.

Figure 3. Spermatozoa with Nomarski and Hoffman optic systems at different magnifications. (A) Nomarski differential interference contrast at ×1000 magnification (×100 DIC objective). (B) Nomarski differential interference contrast at ×12,000 magnification (×100 DIC objective plus VarioC-mount Zoom). (C) Hoffman modulation contrast at ×400 magnification (×40 HMC objective). (D) Hoffman modulation contrast at ×1000 magnification (×40 HMC objective plus VarioC-mount Zoom). Short arrow: small vacuoles; long arrow: large vacuole.

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